Use finer-grained checking in cold mode

third_party/WebKit/Source/core/editing/spellcheck/ColdModeSpellCheckRequester.h

 // Copyright 2017 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef ColdModeSpellCheckRequester_h
 #define ColdModeSpellCheckRequester_h
 
+#include "core/editing/EphemeralRange.h"
 #include "platform/heap/Handle.h"
 
 namespace blink {
 
-class Element;
 class IdleDeadline;
-class LocalFrame;
-class Node;
 class SpellCheckRequester;
 
 // This class is only supposed to be used by IdleSpellCheckCallback in cold mode
 // invocation. Not to be confused with SpellCheckRequester.
 class ColdModeSpellCheckRequester
     : public GarbageCollectedFinalized<ColdModeSpellCheckRequester> {
  public:
   static ColdModeSpellCheckRequester* create(LocalFrame&);
   ~ColdModeSpellCheckRequester();
 
   void setNeedsMoreInvocationForTesting() {
     m_needsMoreInvocationForTesting = true;
   }
 
   void invoke(IdleDeadline*);
   bool fullDocumentChecked() const;
 
  private:
   explicit ColdModeSpellCheckRequester(LocalFrame&);
 
   LocalFrame& frame() const { return *m_frame; }
   SpellCheckRequester& spellCheckRequester() const;
 
+  // Perform checking task incrementally based on the stored state.
+  void step();
+
+  void searchForNextRootEditable();
+  void initializeForCurrentRootEditable();
+  bool haveMoreChunksToCheck();
+  void requestCheckingForNextChunk();
+  void finishCheckingCurrentRootEditable();
+
+  void resetCheckingProgress();
   void chunkAndRequestFullCheckingFor(const Element&);
 
   const Member<LocalFrame> m_frame;
   Member<Node> m_nextNode;
+  Member<Element> m_currentRootEditable;
+  int m_currentFullLength;
+  int m_currentChunkIndex;
+  Position m_currentChunkStart;
   uint64_t m_lastCheckedDOMTreeVersion;
   mutable bool m_needsMoreInvocationForTesting;
 
   DECLARE_TRACE();
   DISALLOW_COPY_AND_ASSIGN(ColdModeSpellCheckRequester);
 };
 }
 
 #endif